CHITOSAN MICROSPHERES PREPARED BY EMULSIFICATION AND IONOTROPIC GELATION

An attempt was made to prepare chitosan microspheres by an emulsion-ph ase separation technique but without the usual use of glutaraldehyde a s a cross-linking agent. Instead, ionotropic gelation was employed in a w/o emulsion. The effect of formulation factors was examined. The re sults showed that microspheres so formed were spherical, free-flowing, and had smooth surfaces. The rate of addition of counterions was impo rtant. Gelation of chitosan droplets should take place before the dest abilizing effect of the counterions occurred. This effect is associate d with the increase in aqueous phase volume when the counterion soluti on is incorporated.